Side Effects of Growing Up
by ijuinpurples
Summary: Verde has created pills that will allow all the ex-arcobaleno to grow into their original age within a month's time. What they didn't know is that the antidote has side effects. A series of drabbles on how the arcobaleno grow up and bring chaos to Tsuna and co and how Tsuna wept and said goodbye to his last remaining sanity as he deals with them. Ch10: Jaeger was traumatized.
1. Chapter 1:Trigger

**DISCLAIMER: I DO NOT OWN KHR. KHR BELONGS TO AKIRA AMANO.**

Tsuna should have known. He should have asked Irie or Spanner to double check the pills that Verde has created three days ago.

But, no. He didn't. He was too busy weeping for his summer holiday that is going to be full of boss training and paperworks.

(Nono gave him a _quarter_ of his paperworks to Tsuna to help Tsuna familiarize himself with the job of a Mafia boss)

"Sorry, Verde, what did you say again?" The 19 years old Vongola don asked the five years old scientist.

"The pills apparently have side effects after all."

"I thought you claimed that there won't be any side effects!"

"I have missed those data due to technical errors."

Tsuna face-palmed. How did a scientist like Verde could make such a mistake? "And what are those side effects?"

Verde looked at his report. "Since we are going to grow from a child body into an adult body within a month, there's a probability of 0.0005 that we might have temporary mood swings or change in behaviour from the sudden rapid growth and hormonal change."

Tsuna groaned. He doesn't want to know what his tutor having mood swing would be like.

"Oii, instead of wasting time here, why don't you go create something to counter the effects then?" Gokudera questioned.

"I can't. The effects are most likely different for each one of us due to our flames constituent and other factors. By the time I finish the antidote, we have already pass through those effects. Besides, as long as there's no trigger to activate those, we'll be fine."

"What trigger?" Yamamoto asked.

"Unfortunately, I don't know either."

The room temperature suddenly dropped by a few degrees. And Tsuna's pen snapped into half.

Gokudera and Yamamoto gulped. This was the first time (and won't be the last time) they saw Tsuna broke something outside of battle.

The ex-lightning arcobaleno immediately took the chance and fled away for his own safety.

"Verdeeeeeeeee!"

* * *

A/n: The ex-arcobaleno are now around 5 years old. If you are wondering why they ate the pills created by Verde without any doubts, it is because they wanted to turn back to their own age as soon as possible. And more importantly, Yuni trusts Verde.


	2. Chapter 2: Mapo tofu

**DISCLAIMER: I DO NOT OWN KHR.**

Summary: Verde has created a pill that allow him and the rest of the arcobaleno (except Yuni and Lal of course) to grow to their original age and size. What everyone didn't know is that the pill has a terrible side effect (on Tsuna's sanity).

* * *

Surprisingly, Fon was the first arcobaleno that succumbed into the side effect of the pill.

Tsuna should have noticed something was wrong when Fon, who was now in his 10 years old body, didn't have his usual serene smile on his face when he greeted him.

"What's wrong, Fon-san?" Tsuna asked.

"I'm craving for mapo-tofu."

"Well, I'll ask the chef to prepare it for you for lunch then."

"But, I still can't eat those without tearing up in my current age. It's still too spicy for me to handle. But, I want to eat it now." Fon frowned.

"Then, I'll ask the chef to make it milder."

-Lunch time-

"So, Fon-san, how was it?"

"….."

"Fon-san?"

Fon's eyes turned watery. And the fork that he was holding engulfed in storm flames in the next second. So was the whole dining table.

"Whoa, cool down, kid." Yamamoto immediately doused rain flame over to calm him down.

Fon blinked and his face turned red from embarrassment. He immediately left to calm himself down.

Tsuna stared at the remains of the table. "I'm really glad that Verde invented that reality illusion gloves."

(Because it is better to use table made from illusion than buying a new one if it is going to get destroyed again)

If Tsuna's mind wasn't too preoccupied with his first boss meeting that he was going to have next week, he would have realised that Fon's trigger has already been activated.

Tsuna's return from his two days' meeting trip was greeted by the destruction of his mansion's east wing and specifically, his office where all his paperworks and homeworks are in there.

If it weren't for Gokudera and Yamamoto who immediately tackled him down, he would have gotten blast off by a huge wave of storm and cloud flames since he was too stunned to move.

In hindsight, Tsuna would have let himself got blasted off and ended up in hospital if he knew what's going to happen within the next few days….or weeks.

"Wao, there's two Hibari?" Yamamoto was the first one to stand up and ask cheerfully.

"You baseball-idiot! That's teenage Fon!" Gokudera said as he helped Tsuna to stand up. He then turned towards Fuuta who was running towards them. "What happened?"

"Hibari-san got mad because Fon-san was disturbing his sleep by nagging at him about mapo tofu non-stop. And Fon-san got mad because Hibari-san ignored him. And both of them ended up fighting." Fuuta said between his gasps for air.

Tsuna remained awfully silent as Yamamoto tried to shout out to the fighting duo to stop.

"Juudaime, should I call Bucking Horse to rein in Hibari?"

"Dino-san huh?" Tsuna suddenly brightened up and smiled. "Ne, Hayato, Dino-nii always claims to be my big brother right? And brothers always share moment of _joys_ right?"

"Yes? Hmm… Juudaime?"

"It's all good then." Tsuna then took out his phone and phoned someone.

"Mukuro, would you come meet me now? I have a favour to ask you~~"

Mukuro materialised himself within seconds. He took a look at the fighting duo before eying the smiling Decimo. "What is it, Tsunayoshi?"

"I allow you to _play_ with Fon and Kyoya if you bring the two of them to visit Dino now."

"Why would I do that if I can play with them _right now?_ " Mukuro asked with a hint of amusement in his voice.

"Well, I'll also allow you to possess my body for one day if you make sure the two of them accompany Dino until Fon is back to normal."

And that's how Dino got to _enjoy_ stormy cloudy weather with a tinge of mist in his mansion for one whole week.

* * *

A/n: Just to clarify, the triggers and the side effects and the duration of it for each arcobaleno are different. You are actually welcomed to guess or even suggest the triggers or the side effects in the review because I'm free to take up requests for now. ^_^


	3. Chapter 3: Art time

**DISCLAIMER: I DO NOT OWN KHR.**

A/n: First part happens on the same day Fon and Hibari fought.

Tsuna didn't even bat an eyelash when he saw Verde was smeared with paints all over his body the moment he entered the main hall.

Or the fact that half of the wall was painted with ridiculous drawing.

(He was still mourning for himself because he has to redo those destroyed paperworks.)

"So, you got triggered just like Fon."

"No. I'm just merely discovered my true inner self. As the second coming of Leonardo da Vinci, I should indulge myself-"

Tsuna rolled his eyes and tuned off the 12 years old artist.

Arts and paintings can't cause any destruction.

At least, that's what Tsuna thought until two days later.

Tsuna was curious why almost everyone he met blushed and avoided eye contacts with him when he walked down the hallway to his new office.

He has a feeling he didn't want to know why but after seeing Ryohei carried his fainted (and still nosebleed) storm guardian to the medical ward for blood infusion, he ended up asking Yamamoto who was standing nearby.

Yamamoto gave him a few sketches that were drawn by Verde. "Ohh, Gokudera fainted after he read this."

Tsuna stared at the sketches.

Reborn was having fun watching a flabbergasted and mortified Tsuna.

"Did you like my art work? Those are my first draft." Verde was leaning by the door side while holding a pen.

The papers on Tsuna's hand were on fire. "Your first draft?! That's mean you have more?!"

"Of course I have. You want a fluffy one or the erotic one? Both have you as the uke -"

Good thing that Verde was just a robot because it was burned to char by a very mortified Tsuna.

He was a millisecond away from burning the whole mansion to get rid of all the copies that Verde has created and hide.

It was thanks to Chrome that volunteered to help him by using her illusion and the realistic illusion glove to get rid of _all_ of those that Tsuna managed to calm down.

Chrome did destroy all of it except the one in her possession…..and the one with Reborn…and Byakuran…..and Enma…..and…..Varia.

(Dino will get one copy later courtesy of Byakuran because no one is suicidal enough to go anywhere near Chiavorone mansion or whatever the remaining of it at the moment)

A/n: I'm sorry but I won't be able to update for possibly one or two months. Some urgent stuffs suddenly come up and I need time to deal with those. I promised I'll update as soon as I settle my problems.

(I wish Doraemon was real. I really need him now. Or heck, I just need Mukuro)


	4. Chapter 4: Girls and pink

**DISCLAIMER: I DO NOT OWN KHR.**

A/N: Mammon is a girl in this chapter. But, I'm also going to write a special/bonus chapter in which Mammon is a boy. This drabbles going to have a lot of bonus chapters. Also, warning: colourful language ahead in this chapter.

* * *

Xanxus almost blanched when he woke up to see the whole mansion has been refurbished into a f****** pink mansion with cute theme in just one day. He never know that there can be so much pink in one place. "What the f***!"

- _Sprink-_

A whole packet of pink glitters appeared out of nowhere and dumped onto his head. "The f*** is this sh**!"

Another load of glitters was dumped onto him. This time, indigo coloured glitter.

"No swearing around, boss. Mammon has made it so that anyone who cursed in this mansion got that on them." Lussuria chirped in with a smiling 10 years old Mammon by his side.

Xanxus blinked. And blinked again. Holy c***. The inverted V-shaped mouth of Mammon has turned upside down. He promptly fired a blast towards them to make sure he wasn't dreaming or trapped in a stupid illusion.

And Mammon doesn't take kindly of his action because half of the room was destroyed by the blast along with her giant Hello Kitty statue. So, she casted an illusion of a black dress with orange embroidery and long silky hair on Xanxus and wouldn't dispelled it until he apologised.

Levi fainted right there and then while Lussuria cooed at his boss.

Xanxus felt like killing his mist guardian but he has a feeling that it will only cause him more troubles later. But, like heck he's going to what's the word again? Ohh, apologise.

So, that left him with only one option. "Dispel this sh** immediately and you get to decorate my office (which was the only place left unfurbished)."

Well, the illusion was dispelled but nevertheless, by the end of the day, the Varia boss was covered in all sorts of colourful glitter.

Xanxus was going to need a lot of alcohol to burn away the images. Heck, he was considering asking Fran to erase his memory. He ended up staying with Nono until the whole crazy ordeal is over.

(In hindsight, he should have seen this coming when Verde send him a copy of his special artworks and when Squalo immediately took another long mission after seeing that although he just came back from one an hour ago.)

Oh, he so going to f****** kill Verde after all this is over. Also, he is going to have a certain shark as his dinner.

* * *

The only one who enjoyed this new (but temporary) change in Mammon is of course the one that (accidentally) triggered Mammon. Lussuria haven't thought much when he absent-mindedly complained about how Mammon always wears her gloomy dark hoodie outfit.

So, when Mammon appeared in front of him in a pink frilly hoodie, he was shocked and speechless. But, the feeling turned into happiness when he finally have someone in the Varia who (temporary) willingly going shopping for adorable clothes and talked about fashion and all the other girly stuffs with him.

Bel and Fran tagged along with the shopping trips just to waste Mammon's money on useless things. They can't wait to see how she will react when she finally snapped out of this effect.

* * *

When Mammon stopped by the half- destroyed Vongola mansion and gave everyone presents (free of charge) with a smile on her face, Tsuna immediately fled to the underground laboratory.

"Teach me how to hack."

"You're just joking, right?" asked Irie.

"No, I. Am. Dead. Serious."

"Sure. I can teach you," said Spanner.

"Spanner! No! Ouch, my stomach hurts!"

"Why not? We're already in mafia, Shoichi." Spanner then turned to look at Tsuna. "By the way, what you want to hack?"

"My father's account. Probably also those old Vongola's higher up."

"….."

"I'm running out of money." Tsuna deadpanned.

"Shouldn't you ask directly from your dad?"

"My father married to his work. I might need to prepare paperworks to ask money from him. It's too troublesome."

"…."

* * *

A/N: I think this drabble is most likely be a monthly update for now since I'm in university now. It could be more after I deal with my problem (which until now, haven't yet thanks to a certain person or department). The Zootopia movie was damn right about the workers' efficiency in the department (the sloth part).

Next chapter is going to be about Skull.


	5. Chapter 5: Rescue mission

**DISCLAIMER: I DO NOT OWN KHR.**

Enma thought that the antidote must has made Skull matured as he didn't even try to piss off Adelheid like what he usually did. Instead, he was behaving like a good little sweet boy like Fuuta.

So, when Enma brought Skull to a seafood restaurant, he didn't expect the 9 years old ex-cloud arcobaleno to burst into tears and wailed around like a baby.

Enma didn't know how to comfort a crying kid. "Waahhhh, don't cry, Skull. What's wrong? Please don't cry. Please…." He practically kneeled and begged Skull to stop crying.

(Despite being 19 years old, Enma always have a panic attack whenever someone cried especially kid.)

He was so close to being reduced into a panic sobbing mess as well when Rauji and Lambo passed by.

Rauji was good in interacting and comforting kids. Lambo was a good example. It only took one minute for the Simon mountain guardian to calm Skull down.

By the time he stopped crying, Skull was burning with a certain resolve in his eyes. (He didn't wear his helmet by the way)

Unfortunately, only Lambo saw his resolve and he decided to join Skull in whatever he was planning to do since he was bored. _This is going to be very fun._

* * *

Three days later,

The whole Italy was in an uproar when all the seafood restaurant was attacked by armies of invincible human size kraken that dropped from the sky.

Inside an airship, 14 years old Skull gave Lambo a high five before turning towards his monitor.

"Ha, serve them right! How dare they make Oodako's relatives into dishes!" said Skull as he continued to observe the attack through that monitor.

* * *

Enma tried to destroy all the krakens but it's a tough self-appointed task since the kraken was coated with a layer of lightning flames and they propagated non-stop.

And he's all alone since all his guardians (except Adel who went to kill Skull) were quick enough to run away in the excuse of evacuating the civilians.

He decided to call Tsuna for help.

Unfortunately, his call weren't answered. He didn't need any hyper intuition to know that Tsuna purposely ignored his call. And a tick mark appeared on his forehead followed by a brilliant idea. He smiled in amusement.

* * *

Tsuna was learning how to hack when his phone rang. He was about to answer the call when he saw the identity of the caller. _Wait a minute. Enma lived with Skull. And Skull is one of the arcobaleno who drank the antidote._

Nope. He's not going to answer that call. If he has to suffer this, Enma has to suffer too. That's what best friends are for. Suffering together.

"Errr, Tsuna? Your phone." Irie winced at the sight of the melted phone in Tsuna's hand.

Tsuna tilted his head slightly. "Yes?"

"Your phone is melting in your hand."

"So what? I need new phone anyway."

"I think you really need a break from your work, Tsuna."

"Why? I'm feeling perfectly fine. If anything, you should be the one to take a break. You spend all the time in the lab."

"…"

Irie prayed for Tsuna in his heart. He really didn't want his only sane friend (beside the girls) in the Vongola to fell into the same category as anyone else (which always has a few screws loose).

* * *

That night, when everyone in the Vongola mansion was asleep, a few black holes appeared in various part of the mansion including Tsuna's bedroom.

Instead of sucking up things, the black holes expelled out hundreds of raging krakens.

And as Tsuna tried to destroy the kraken, a small black hole appeared in front of him and a small piece of note came out.

'A present for you for ditching your best friend.'

* * *

A/n: Next chapter (in two weeks time) is going to be Colonello's turn. ^_^/


	6. Chapter 6: Duck Love

**DISCLAIMER: I DO NOT OWN KHR.**

It all began five days ago where Tsuna and the rest was having their first monthly Animals Appreciation Day where everyone was forced to watch animals documentary for the whole day. (There was also Nami-chuu Appreciation Day and Namimori Appreciation Day too.)

These were all 'requests' from Hibari as a compensation for him to leave his beloved Namimori to carry out his duty as Tsuna's Cloud Guardian.

Nobody was suicidal enough to refuse those ridiculous celebrations (except for Mukuro).

Hibari even ceased his fight with Fon temporarily in Dino's mansion for the sake of this.

Colonello who visited Tsuna at that day was dragged along to watch the documentary. Somehow along the way, the eight years old ex-rain arcobaleno began to think that he was a duck.

Tsuna groaned and smacked his head. "Why on Earth did you think you are a duck out of so many animals?"

"Ducks are yellow and like water."

"So?"

"I'm blond and I have rain flames."

"Then, I'm a duck's pupil." Ryohei declared suddenly. "Hey, we are extreme ducks buddy, Takeshi." Both of them high-fived together. Lambo was rolling on the floor laughing his head off while Gokudera mumbled under his breath about why everyone except for Tsuna and Reborn was an idiot.

Tsuna groaned. He tried to convince him otherwise but Hibari's remarks on Colonello being an herbivore was not helping at all.

* * *

The next day, the little 8 years old boy followed Lal Mirch everywhere like an obedient little duckling following his mama duck.

Iemitsu and the rest of the CEDEF members found it adorable and cooed at the rare sight. (Those unfortunate one ended up in hospital for a month)

The said woman was not the least bit amused by the whole thing. She knew that this was all due to the antidote's side effect but this doesn't stop her from beating her idiot student/lover into pulp when Colonello decided to follow her into the bathroom.

Colonello snapped out of the duck thinking when he turned 15 years old which was just after three days. Lal thought that the side effects have finally ended. She also idly thought about the ridiculous growth patterns from the antidote. What she didn't know was that the sudden growth has made Colonello even more stupid and flirty than his usual old-self.

Colonello proved his stupidity by making the most foolish mistakes in the world. He asked Iemitsu and Byakuran for love advice.

When people asked him later why he chose to ask the duo out of so many people that he could have asked, he told them it was because of his love intuition.

Iemitsu suggested Colonello to do something romantic like giving Lal lots of red roses. Colonello filled Lal's office and house with red roses until it's overflowing out of the windows.

The CEDEF boss also suggested him to dedicate a song for Lal.

Byakuran helped by choosing the cheesiest romantic song out of all the parallel worlds for Colonello to sing.

Needless to say, the moment Colonello sang the first verse over the PA system, Lal blanched and she decided to flee.

* * *

"Sawada, if you tell him that I'm here, I will personally send you off to a trip to he**."With that, she slammed the door against Tsuna's face for the second time that day.

Tsuna snorted. _It's not like I haven't see he**. I'm basically living with a Satan and a bunch of devils. I don't see any difference between here and he**._

And then he blinked and stared dumbfoundedly at his own office door. _Wait a minute, so, did I just get kicked out from my very own office?_

"Oh well, I just go and take over other office then."

"Gao?" Natsu tilted his head sideways while questioning his owner's sudden decision.

"What? That's the fastest way to get myself a new office. But before that, we need to get lots of marshmallows as hostages first."

* * *

It took ten days for Colonello to return back to his normal self. It also worth to note that he still couldn't find Lal Mirch throughout those ten days despite all his intel and his so called love intuition.

* * *

Next chapter: Yey \^-^/ It's finally Reborn's turn.


	7. Chapter 7:Espresso and Cuddle Time

**DISCLAIMER: I DO NOT OWN KHR.**

Reborn is going to kill Verde. He can't believe that the antidote didn't work on him. Or at least that's what he thought since he was the only ex-arcobaleno left that haven't grow a single centimeter after they took the pill since two weeks ago.

He was about to find and give Tsuna extra tor…tutoring when he saw Tsuna taking a nap with Natsu under the tree outside through the mansion's window. Tsuna was cuddling with Natsu and Reborn can't help but think how adorable they were now. _I wonder how cuddling with Tsuna felt like._ And he froze. He was so appalled of that sudden thought that he proceeded to give Tsuna a _special_ Vongola-style wake-up call.

* * *

 **-BAM-**

Tsuna's bedroom door got blasted away by a certain Gesso boss at the ungodly hour of 4 a.m. with a sleepy Yuni tagging along behind him.

"Wakey wakey Tsu-chan. Let's go climb the Alps and watch the sunrise together~~"

"Erghh, what the h***, Byakuran. I need my sleep and you're paying for the door." Tsuna mumbled out and proceed to bury his face in his pillow. He missed the shocked look on Byakuran's face and the blushing on Yuni's face.

"Oh my marshmallow god, how dare you tainted Yuni's innocent! And how dare you didn't tell me that you got yourself a boyfriend already? I thought we're best friends and best friends share good news together." Byakuran sniffed while at the same time covered Yuni's eyes with his hands.

Tsuna's eyes snapped open and he immediately sat up. "WHAT?! I didn't get-" Tsuna's words were cut off when his head got hit by a pillow from behind.

"Shut up, dame-Tsuna. I'm trying to sleep here."

"Hiiee! What? How? Who-" _Wait a second, he called me dame-Tsuna…_ "Reborn? But-"

 **-BANG-**

A bullet whizzed past Tsuna's hair and embedded itself at the wall beside Byakuran.

"It's either you go back to sleep now on your own or I'll help putting you into a permanent sleep." The 15 years old Reborn said gruffly and snuggled deeper under the comforter.

"Looks like you got yourself a grumpy boyfriend, Tsu-chan~"

"Sorry, Tsuna for disturbing your…hmm….sleep with Uncle Reborn. We'll take our leave now." Yuni began to drag the Mare teen away. "Come on, Byakuran. We shouldn't disturb them anymore."

"Ah, wait, Yuni-chan…" He was pretty sure the both of them have misunderstood him but he never got the chance to call the duo back when Reborn unconsciously pulled him to the bed and cuddled with him. Tsuna fainted from the sheer shock of it because Reborn never cuddle and _omg, Reborn didn't put on any shirt_.

* * *

Tsuna thought the cuddle thing and Reborn sleeping on his bed was just a nightmare. Until he woke up just in time to see Reborn left his room with a bad mood aura surrounding him. He idly wondered about the crazy growth rate pattern of the arcobaleno. Reborn practically grew from a five years old boy to fifteen years old teen in a single night. He really has to make sure he stayed away from Verde's creation.

The sudden growth and the change in hormones has made Reborn's killing mode on almost majority of the day. The only thing that can calm him down was the espresso brewed by either Nana (which unfortunately was in Japan) or Tsuna.

Sufficed to say, nobody in the mansion was suicidal enough including Hibari and Mukuro (after they learnt their lesson of course) to go anywhere within 500 meter radius from the ex-sun arcobaleno.

This was also probably the only good news for Tsuna because all his guardians were smart enough to not cause chaos or destroying any part of the mansion in case Reborn exploded on them.

On a second thought, he really shouldn't have jinxed himself. It just happened that the day Reborn ran out of expresso was the day everyone seems to have business with him – his guardians, the Varia, the Simon, Byakuran and the arcobaleno; Skull and Colonello who was still under the influence of the antidotes.

Reborn was not amused by it. He wanted his espresso.

"Tsuna is mine and he's going with me, so, f*** off." Reborn began to drag Tsuna from the chaos in the main hall caused by all the groups of people.

"Ushishishishi, the prince comes first."

"The brat isn't going anywhere till he pays back all the money that I have spent under the antidote's influence."

"But, Reborn, Tsuna is going to watch the baseball league with me today."

"Tsuna needs to help me find Lal, kora."

"I need Tsuna to help me save all the relatives of Oodako and take over the world."

"That's not fair. You can't keep Tsu-chan for yourself every day."

Tsuna winced. It seemed like there were still people who wanted to die a painful death. He didn't need his hyper intuition to tell him how much his mansion would survive. (You should worry more for your friends instead of your mansion, Tsuna)

* * *

The cuddling at night still continued though after the _little_ massacre and Tsuna might or might not have taken a liking onto that new sleeping habit of Reborn who was surprisingly warm and a good cuddler. (Tsuna always thought that Reborn was cold-blooded)

* * *

"That was obviously pure jealousy and possessiveness. And you said that you both aren't dating each other." Byakuran pouted as he lied on his bed with his whole body covered in bandages.

* * *

A/n: I'm kind of busy with my university life currently and I only have time to write this in my phone during my lunch break. So, I can't update this drabble series regularly.

But, the good news is this series still have at least 10 more special chapters to go before it is complete. Some of them are chapters for Reborn and Fon and Mammon (boy). Might also do a chapter on Bermuda if I have any idea pop up in my head. (Ideas are welcomed)

(I actually already plan for this chapter since the beginning of this series but the part with Byakuran only came up a few days ago XD. Also, in case you have read Happy Birthday KHR series, this series is not related to the chapter 3.)


	8. Chapter 8: Playful storm

**DISCLAIMER: I DO NOT OWN KHR**.

A/n: From this chapter onwards, all the chapters will be under special chapters category. It means that it's not related to the first seven chapter unless stated so.

This is another version for Fon.

* * *

~Wind can be gentle and calm or a raging storm. But, people tend to forget, wind can be teasing and fun as well~

* * *

Fon was in the process of packing his stuff to officially move into the Vongola mansion when he stumbled upon an old album.

 _Ah, how nostalgic. I almost forgot that Kyoya is such a cute little nephew when he was small._ Fon smiled fondly as he flipped through each page of the album.

* * *

Tsuna didn't think much when he invited all the ex-arcobaleno to live with him in the newly built Vongola mansion. So, when he found out that Verde's antidote might have some side implication, he prayed to God as much as he could. _Please let me survive through this disaster._

* * *

"Ouch!"

It was a soft 'ouch' but nevertheless, it managed to reach Tsuna's ears who immediately looked out from his window out of curiosity. It took all his dying will to stifle his laugh as he quickly hide himself behind the curtain.

He never thought that he would see this day coming. Hibari Kyoya, the great Namimori demon fell into a pitfall trap and let out a 'Ouch'. _This is the best day of my entire life. This is pure jackpot._

Tsuna thought it was Mukuro that set up the trap because no one was suicidal enough to play a prank on Kyoya. But, his thought went down the drain when he heard someone laughing.

 _Is that Fon?_ Tsuna squinted his eyes through the gap of the curtain to get a better look. _Oh my God, it is Fon. Is he drunk?_

The thirteen years old Fon was couching on the ground holding a camera while laughing at his nephew who was trying (and failing) to get out from the pitfall.

"That little 'ouch' of yours is cute as always, Kyoya. Never thought I did hear that again." Fon wheezed.

"You better get me out of here if you still want your body to remain intact." Kyoya practically seethed through his words as he glared deadly at Fon.

"Aww, I thought a mere greasy surface won't stop you from getting out of there, Kyoya." Fon continued to giggle and remained unaffected by the murderous aura as he snapped another photo of Kyoya who was covered with colorful feathers and grease.

* * *

Apparently, the antidote has turned the growing ex-storm arcobaleno into a childish suicidal maniac. There was because no one in their right mind would dare to prank Kyoya. Or Mukuro.

The said illusionist thought that he has managed to escape from Fon's prank that morning when the martial artist tried to shoot paintballs at him until he walked down the aisle and saw everyone burst into laughing the moment they saw him.

"Haha, Mukuro. I didn't know you like pineapple so much that you cosplay as the fruit." Takeshi laughed while wiping away his tear.

"Pineapple head to the extreme!"

Mukuro immediately materialised a mirror and proceeded to stare in horror and disappeared into a shroud of mist when he saw his own appearance.

His hair was dyed with yellow colour and somehow the top end of his hair was in green colour. _Just wait until I get my hand on you, Fon. I'll made sure you turned into a nice mapo tofu._

Unfortunately, Mukuro was so fixated with turning his hair back into the original blue color that he didn't noticed a paper stuck to his back that said ' _I'm a walking pineapple'._

Tsuna was sure that Fon took photos of Mukuro too. He made a mental note to get a copy of the photos from Fon. It never harm to have blackmail materials against his own guardians for his own safety.

* * *

Naturally, when there's fun and pranks around, there's where one can find a certain marshmallow lover.

With Byakuran and Fon working together, it's just a matter of time before everyone got pranked and experienced the most mortifying moment in their entire life.

Therefore, when Tsuna somehow found out that the catastrophic duo planned to prank Reborn, he decided to join them.

 _Why bothered to stop them if I'm going to get killed by Reborn anyway (for letting this happened). I want to have my share of some fun too before I die with my pride intact (Tsuna hasn't get pranked yet)._

* * *

~Two days later~

The _peace_ in the mansion was broken by the scream of a certain hitman followed by the sound of guns and explosion. Everyone was smart enough to fled away from the east wing except for Fon who was rolling on the floor laughing while dodging a hailstorm of bullets.

As for Tsuna and Byakuran, it was a double miracles that they managed to escape from Reborn AND fly to Yuni's mansion to seek refuge without crashing into something with the way they laughed while flying at the same time.


	9. Chapter 9: Family drama

**DISCLAIMER: I DO NOT OWN KHR.**

A/n: Sorry for the late update. _ Thanks for reminding me, **xXGod707Xx**. Between assignments, study, game, fanfic, anime and manga, I got distracted and totally forgot that I said I want to update this in January.

* * *

The very first thing that Tsuna did when he dashed through the door of the police station was to clasp the police officer's hands and stared at him while gasping for breath. "Please….please tell me-"

"Calm down, they are perfectly fine and safe. Nothing happened to them." Eddie, the police officer, smiled to reassure him although his plan backfired as Tsuna became more panic.

"Not them. I'm worried about you. Are you alright? Please tell me you are alright. What's one plus one equal to?" _Sane person wouldn't smile in the presence of those people._

"What? I-" Before Eddie could say anything, a certain marshmallow addict interrupted him.

"Tsk tsk tsk, Tsu-chan. You're such a bad mum. Instead of someone that you never meet before, you should be more worry about your two sons here." Byakuran gestured at the two little boys beside him.

"Ushishishi, how dare you put someone else before the prince?"

"More like your mum ditch you guys." Nosaru laughed at his seat.

"Boooo." Bluebell who was hugging Byakuran jeered at both Bel and Mammon.

"Muu, did you hate us, mama?" The eight years old ex-mist arcobaleno clutched onto Tsuna's arm and sniffed.

He has the sudden urge to bang his head on the nearby wall and fainted right there and then.

"Urgh, let me guess. You're the one that trigger Mammon, isn't it, Bel?" Tsuna said as he remained unfazed by Bel, Nosaru and Bluebell who appeared in their 10 years old form. _Must have been_ _Mammon's illusion._

"Ushishishi. That's right. It only took the prince one try to trigger him. Aren't you proud of me, mama?" Although it was only by pure chance that he did managed to trigger him. He didn't expect his casual remark on how Mammon should enjoy his 'childhood' instead of being gloomy like usual would be the trigger.

Tsuna sighed before he continued. "I don't even have custody over you. Shouldn't Xan-" He shook his head. "Shouldn't you call Lussuria to handle this? Heck, even Byakuran can bail you out!" He pointed accusingly at the Gesso boss who was happily gulfing down the marshmallow as though he was just drinking water.

"They are your children, not mine. (Varia is under Vongola) Unless *gasp* Tsu-chan finally willing to accept my love-"

"Papa exploded the moment that police officer phoned him." Mammon cut off Byakuran's words and gestured at Eddie who winced as he recalled the colorful string of words the moment he mentioned both the kids' names to Xanxus in the call. He has no idea one can use so many cuss words in a single sentence.

"Mama Luss is out on her shopping spree while mama Squ is out f***ing people with his sword." Bel continued as though it was a normal thing to a 'child' would say in the police station.

Eddie stared dumbfoundedly at the family in front of him. _He didn't get what they are talking at all._ _They sounded like a very complicated family._ And he has a feeling he didn't want to understand either. So, he just handed Tsuna and Byakuran a form to sign before letting the kids go.

"What did the kids do to get caught here anyway, Mr. Officer?" Tsuna asked as he signed the form.

"They are disturbing the public by having paintball fight in the middle of the street."

The brunet bumped his head onto the table while Byakuran complained about why he was not invited at the back.

"Are you okay, miss?" Eddie asked in concerned when Tsuna refused to lift his head from the table.

Tsuna's eyes snapped open at his title. "WHAT?!"

* * *

"Aww, Tsu-chan! You look so cute when you pout like that especially in that cute dress of yours." Byakuran poked his cheek as the six of them walked by the street.

Tsuna glared at the Gesso boss, then to the rest of them. He couldn't believe that he didn't notice Mammon put an illusion on him. And the worst of all, the little mist refused to lift up the illusion because Byakuran said so.

"Good kid listens to adult. And Byakuran is older than you, mama."

"But, you call me mama. And good kid doesn't get into paintball fight in the middle of the street."

"Tsu-chan~~ I'll ask Mammon-kun to remove the illusion if you say 'I love you~'"

Tsuna stared impassively at Byakuran and a sudden idea popped up in his mind.

'A mafia boss never does things half-ass.' That's what Reborn always told him. It's time for him to apply what he has learnt from his tutor now.

Since Mammon refused to remove the illusion, he might as well make good use of it. He stopped walking and clutched onto the hem of his illusionary dress.

"Tsu-chan?" Byakuran tilted his head in confusion.

Tsuna took in a deep breath and stared at the ground. Big fat tears came rolling down his cheeks as he began to sob loudly in the middle of the walkways.

"I….I don't mind –hic- if you want to – hic- get another –hic- wife. I don't mind if –hic- your brother and sister are bullying me. –hic- I want to remain by your side. –hic- Please don't ditch me." Tsuna said between his sobs.

His cries have attracted the attention of almost everyone in the street. The mischievous Mammon immediately sided with Tsuna and cried along with him. "Papa, please don't abandon mama." He shook Byakuran's hands.

Bel quickly caught on and said. "The prince doesn't want the peasants' mother to be the prince's mother." He pointed accusingly at Nosaru and Bluebell.

Byakuran's jaw dropped. Nosaru choked on his drinks on Bluebell.

Bluebell shrieked. "Ewww. What the he** is wrong with you?"

"It's not my fault. It's Tsuna's fault."

And Tsuna cried further at the mention of his name. He smirked internally when he saw majority of the passer-by were now glaring daggers at Byakuran. One of them even offered him tissues to wipe his tears away.

 _Reborn must have been very proud of me._

* * *

A/n: Reborn has totally corrupted Tsuna…..

On a side note, there are roughly five more chapters to go before this end (I think). I just need time to transfer those into my laptop since I wrote them in my notebook, which I have no idea where I put it….


	10. Chapter 10: Camaraderie

**DISCLAIMER: I DO NOT OWN KHR.**

A/n: This chapter is not much on Tsuna but I have been very tempted to write this for months already XD

* * *

What has he done to deserve this? Jaeger groaned.

No.

That didn't sound right. What have the others done that they didn't deserve this?

Why was he the only one that was not affected by the side effects of the antidote?

Jaeger sighed for the umpteenth time and received a pat on his shoulder by the redhead in return.

Enma casted sympathy looks towards Jaeger. "Well, look at the bright side. At least, you gain back your normal human look."

"It's not worth it. Not with the mental scar that I have to live through the rest of my life." Memories of yesterday's event flashed through his mind again and he banged his head against the wall to stop them.

Mental scar due to the arcobaleno curse was one thing. This was another thing (and whole new level) altogether.

* * *

 **FLASHBACK STARTS**

Tsuna thought that since Verde was going to create antidote for the ex-arcobaleno, why not create another antidote that could help the Vindice to regain their human appearance.

After all, no one wants to live for eternity with a zombie-like appearance.

He should have waited for the ex-arcobaleno to return to their normal age before asking Verde to create the antidote for Vindice.

Nevertheless, the ex-arcobaleno has kept him so busy that he forgot to inform the Vindice that there might be side effects for the antidote that they took.

* * *

It all started simple enough.

Jaeger should have known something was wrong when he saw Bermuda giggled. His boss never giggled. The glint in his boss did not bode well with him at all.

He shouldn't have let the matter slide and continued his work.

* * *

The sight of Big Pino dressing up in a blue frilly dress and tried to flirt with him would forever haunt him for the rest of his life.

The sight of Small Gia performing a strip dance made him wanted to burn his own brain to ash.

Bermuda….. Jaeger shuddered. His boss was the worst.

The only consolation that he has was he was not the only one who was traumatised. Somehow, all the Vendice's members have decided to host a party and invite (kidnap) the mafia bosses to their party.

At least, the mafia world would be in peace for quite some time after this.

He just has to make sure that his colleagues didn't invite the Gesso boss or Reborn. He didn't need people to feed his current boss nor the rest of the Vendice any more crazy ideas.

Too bad, lady luck was not by his side.

* * *

When Byakuran somehow invited himself to the party, Jaeger knew he has to take action fast if he wanted to save his already traumatized soul and prevent the Vendicare from collapsing. Somewhere at the back of his mind, he idly wondered if this was still call a party if more than half of the people were perpetually frozen or scared to death.

So, he decided to call for help from Vongola Decimo to rein them in. Perhaps, freeze all of them using Zero Point Breakthrough until the side effects wore off.

Unfortunately, after dealing with the ex-arcobaleno's antics for two weeks, Tsuna has learnt that it was far much easier to roll with the punches instead of trying to stop people.

Thus, it was not a surprise when the first thing that Tsuna did when he saw the party after getting out from Jaeger's portal was to invite himself in and teamed up with Byakuran in what seemed like a snowball fight between them and Alejandro and a dozen of Ginger Bread.

 _WHAT?! I thought you are the sane one here, Vongola Decimo._ Jaeger didn't have time to ponder more when the rest of Vongola Tenth Generation guardians and the ex-arcobaleno appeared out of nowhere and joined the party.

Something suspiciously sounded like a whimper escaped Jaeger's mouth when he saw Reborn and Bermuda act like good old buddies.

That was when he caught sight of the Simon Decimo who was dragged here by Skull.

Both their eyes were locked at each other. He recognized the look on the young Simon's face. It was the one that mirrored his for the past 24 hours.

A bond of camaraderie was formed between them and both of them nodded.

* * *

 **FLASHBACK ENDS**

"That reminds me. What happens to Sawada Tsunayoshi? He looks normal the last time I saw him."

"Who's that? I don't know anyone with that name." The young Simon Decimo sulked.

"I thought you and him are best friends."

"Best friends don't ditch one another when in need." He was still salty about the fact that Tsuna left him to deal with Skull alone.

"…." Jaeger refrained himself from asking what has happened. Whatever it was, it definitely was not good for his current state of mind. He turned towards the other redhead that was lying unconsciously on the other side of the cave. And here was the perk of being the second in command of Vendice. He knew all the underground caves that can be used as temporary hiding that no one else knew.

Jaeger continued to stare at the unconscious figure. That guy has fainted when he approached him and Enma insisted to bring him along. _Who is this guy again?_ He seemed to recall that that guy was also present in the arcobaleno battle fiasco.

"He is Byakuran's best friend, Irie Shoichi. Don't worry, he is normal just like us. That's why I picked him up. He's probably going to wake up soon."

Unknown to both of them, Shoichi has actually woken up just now but fainted again when he saw Jaeger was banging his head on the wall. Nothing good ever came out when someone was banging their head. So, if the Vindice's Strongest Warrior was banging his head, it meant a disaster was happening. At least, that was what Irie's mind supplied to him before his stomach ache did its job.

* * *

A/n: I don't have internet access for the next two or three weeks, so I will update this and Sky Arcobaleno Duo next month.


End file.
